The dirt path, narrow and steep, snakes about 500 yards up a severe hillside in Danville, Calif., and beckons Maurice Jones-Drew each week. He and his trainer consider it their Saturday morning exclamation point, the grueling capstone for their week of workouts, their version of the "Rocky" steps.

"The first time, I was like, 'If I want to be the best, I've got to get up and run this thing,'" said Jones-Drew, beginning the next chapter of his NFL career, as a running back for the Oakland Raiders. "We ran about 12 of them. That's the work you have to put in."

"Maurice is no-frills. He doesn't need anything fancy," said Mike Blasquez, Jones-Drew's trainer, who is the strength and conditioning coach at Cal, and held the same position at Concord De La Salle High when the running back was a star there. "He just wants to work. The hill he runs is a beast — 500 yards and uphill at 40 degrees. We've run it in the rain, run it when it was hard as a rock."

Another mountain stands in his path. Jones-Drew, coming off foot surgery that preceded a disappointing 2013 season, is determined to prove he still has something left. He's 29, an age when most running backs are either done or on a downward slide, and he's on a team that's filled with question marks, the 4-12 straggler in the AFC West, a division that sent its other three teams to the playoffs last season.

Jones-Drew, the former UCLA standout, has gone from coast to coast — from Jacksonville, where he was the Jaguars' No. 2 all-time rusher, to his childhood home of Oakland, where he's competing with the oft-injured Darren McFadden to be the No. 1 back. The Raiders stage their annual three-day mandatory mini-camp this week.

After winning the NFL rushing title with 1,606 yards in 2011, Jones-Drew's 2012 season was cut short after six games by an injury that required two screws to hold his left foot together. He had to relearn how to walk, then how to run, and was limited to 803 yards rushing last season. The Jaguars, in turn, let him test the open market, and Jones-Drew — who also talked to the Pittsburgh Steelers — signed a three-year deal with the Raiders in March.

"For awhile, I was contemplating retirement because I just didn't feel like I had it anymore," said Jones-Drew, who averaged 3.4 yards per carry last season after seven years of never averaging fewer than 4.2. "But that wasn't the case. My trainer helped me get back in shape and gain that foundation that I'd lost with the surgery."

So intense were those workouts, which began in the second week of January, that Jones-Drew threw up on each of the first five days, even though he wasn't doing any running or lifting of heavy weights. He needed to know if he was still passionate enough about the game to push himself to the brink of collapse.

"I wanted to see if I still had that burning desire," he said in a phone interview this week. "When you throw up five days in a row and keep coming back, you're like, OK, there's still something there."

Passion only counts for so much, however. Jones-Drew holds no illusions about the difficulty of the task he's facing. When he first arrived at Oakland he even acknowledged the lingering joke about the franchise, that it had a great roster — great for 2009, that is.

At this time of year, optimism is cresting with all 32 NFL teams, so it's not entirely surprising that Schaub recently proclaimed the backfield tandem of Jones-Drew and McFadden "is as good as I've been around in all my years."

In an interview on SiriusXM NFL Radio, the Raiders quarterback — who played with an impressive backfield of Arian Foster and Ben Tate in Houston — called the ballcarriers who now will line up behind him "a great one-two punch, the combination of speed and power that they operate with, and also being smart in the protection game, being able to line them up out wide on linebackers and have them be able to run all the different routes on the route tree."

For the most part, though, there is little buzz in NFL circles about Oakland's backfield.

Throughout his career, the 5-foot-7 Jones-Drew has used doubters as rocket fuel, taking great pride in making skeptics look silly. But in recent years, the criticism has stung a bit more.

"It doesn't bother me that people have written me off, but it's just how they've done it," he said. "I understand if I had played bad the year before, then played the way I did [in 2013]. Then, I could understand people saying, 'Oh, he's done.' But I was leading the league in rushing before I broke my foot.

"It was tough hearing people say, 'Aw, you don't have it anymore.'"

Maybe for the first time, he too questioned himself, searching for that explosive burst that was so obvious earlier in his career.

"I watched the same tape and I'd say, 'Man, why'd I do this? Why didn't I do that?'" he said. "Part of it was, just physically, I wasn't able to do some of the same things I'm used to doing. But once I started working out after the season . . ."

And it was more than simply working out. It was working out without feeling injured, for the first time in ages, and getting a fresh start in a familiar and comfortable place.